This book constitutes the refereed proceedings of the 8th International Conference on Data Warehousing and Knowledge Discovery, DaWaK 2006, held in Krakow, Poland in September 2006 in conjunction with DEXA 2006.The 53 revised full papers presented were carefully reviewed and selected from 198 submissions. The papers are organized in topical sections on ETL processing, materialized view, multidimensional design, OLAP and multidimensional model, cubes processing, data warehouse applications, mining techniques, frequent itemsets, mining data streams, ontology-based mining, clustering, advanced mining techniques, association rules, miscellaneous applications, and classification.